At first, students on the left were full of hope about the 1968 election.

I am a New England regional organizer for Students for a Democratic Society (SDS), the largest New Left student organization spearheading the opposition to the war in Vietnam. Living in Cambridge, I swim in a river of others just as young and just as committed — committed to ending the war in Vietnam; committed to radical change for black Americans; committed to creating an American New Left, rooted in American realities and traditions. But in this year of 1968, what we most want is to end the seemingly endless war in Vietnam, a responsibility that rests uncomfortably on our too-young shoulders.

The weight of the damn war presses down upon us. Day after day, each week, each long month, we carry it with us, though we don’t experience the savage horrors of those who actually fight in it. Images, facts, lies, replay in our minds, in our dreams. A silent monk in flames. American boys dying in tall elephant grass. A naked girl running from inferno towers of napalm, arms extended, mouth open, silently screaming. … A war measured in nightly "body counts."

A friend’s cousin from Ohio, a first lieutenant, dead in the Ia Drang Valley.  Napalm, jellied flame, jellied death. Endless lies. Escalation without end. Willie Pete — white phosphorous that burns to the bone, burns even in water, burns unchecked when exposed to the very air we all breath. Agent Orange. Waves of B-52s dropping 7 million tons of bombs on Vietnam, Laos, and Cambodia — more than twice the amount of bombs dropped altogether on Europe and Asia in World War II.

Uncounted villages destroyed. Uncountable dead. Dead "gooks" who are in reality mothers, daughters, sons, brothers, fathers, and grandfathers. Ben Tre: "We had to destroy the village in order to save it." A million, 2 million, 3 million dead Vietnamese.

Where there should be the exuberant joy of youth, there is a sense of death all around.

1968: a hinge year. History is going to change. What we do will make a difference.

As 1968 unfolds, it seems as if the entire globe is caught up in a struggle between the old and the young, between a tired, bloody present and a very different future. In Prague, reformists challenge Soviet domination and orthodoxy. In New Hampshire, anti-war Sen. Eugene McCarthy challenges Lyndon Johnson, and suddenly Vietnam is the most important issue in the Democratic presidential primaries. The forces of change and of the status quo keep colliding.

On the right, Alabama Gov. George Wallace, he of "Segregation now. Segregation tomorrow. And segregation forever," campaigns as an independent candidate for president, drawing large and very angry and very white crowds. The people turning out to cheer him are experiencing profound change and do not like it.

As McCarthy surges, along with antiwar sentiment, Robert Kennedy finally takes the plunge and announces for president. He campaigns against the war and for a vision of economic justice that appeals to both black and white working and poor families. President Johnson announces he will not run again and will seek a negotiated peace in Vietnam.

Martin Luther King Jr. is assassinated, and America’s urban black neighborhoods from Oakland to Boston erupt in sadness, in anger, in rage and frustration.

We, in SDS and the antiwar movement, have legions of students with us, literally hundreds of thousands. We can play a pivotal role. Some "get clean for Gene" and knock on doors and power the McCarthy "revolution." Others, really only a few, jump into the Kennedy campaign.

Most of us who have built the antiwar movement demonstration by demonstration, dorm meeting after dorm meeting, are so sickened by the corruption of American politics that we refuse to participate. Despite there being two candidates opposing the war, Kennedy and McCarthy, we think American politics has been so corrupted that real change has to come from outside the system.

The rules of the election game are rigged to favor the corporate elites. We are so habituated to being the prophetic minority that we cannot understand that a majority of the country is swinging against the war. We are so disgusted by all we have experienced that we want to "up the ante." We think our job is to create so much disruption that the elites will be forced to end the war. Our slogan is Vote with your feet, vote in the street.

But then reality set in

Student revolts rock Germany and Paris and Mexico. Students led by SDS occupy buildings at Columbia until violently evicted by police. The Soviets crush the Prague Spring. American cities are occupied by the National Guard. Everywhere the forces of the old are battling the forces of the young: The forces of the old include the old men in the Kremlin, the old men in power in Paris, the old men entrenched in Mexico City who will order their troops to fire on students; the old men who run the Republican Party and the old men who run the Democratic Party and have prosecuted the war.

Bobby Kennedy is killed. Once again, the gun will bend America’s future, warp what is possible. Now the leading candidate on the Democratic side is the feckless Hubert Humphrey, once the tiger of liberals, once the "happy warrior," now the soulless candidate of the establishment.

We have nothing but contempt for him. He sold out the Mississippi Freedom Party, the only integrated Mississippi delegation to the 1964 Democratic convention, so that he might become Johnson’s VP. This from the man who first made his name as the spokesperson for integration at the 1948 Democratic convention. For the past four years, he has been a pathetic irrelevancy in the Johnson war White House. Now, with a chance to lead, he refuses to denounce the war.  He makes us sick. Politics makes us sick.

This only gets worse when antiwar protestors "bringing the war home" flood the streets of Chicago outside of the convention hall. The nation watches on television as the Chicago police force flies out of control, riots, and beats anyone and everyone that they perceive as possibly "other," everyone possibly with the protestors. It doesn’t matter; journalists, delegates, family of delegates, younger Congress members — they all are attacked by the rampaging cops with many a score to settle, urged on and unleashed by the profane mayor, Boss Daley, kingmaker, Democrat.

We are disgusted. The Democratic Party is torn apart. Humphrey becomes the nominee.

Richard Nixon becomes the Republican nominee. He promises he has a plan to end the war but will not announce it. He and Henry Kissinger secretly commit treason by interfering with the peace talks in Paris between America and the Vietnamese, making sure there is no breakthrough for peace. Nixon, even before entering the White House, subverts the law, prolongs the agony of the war.

In the wake of the civil rights successes, Nixon adopts the first "Southern strategy," which will reshape the Republican Party, wipe out the once dominant Southern white Democrats, and alter the direction of American politics for decades.

Nixon adopts a law-and-order campaign. He declares to the Republicans gathered in convention in Miami Beach, "As we look at America, we see cities enveloped in smoke and flame. We hear sirens in the night. We see Americans dying on distant battlefields abroad. We see Americans hating each other, fighting each other, killing each other at home. And as we see and hear these things, millions of Americans cry out in anguish: Did we come all this way for this?"

Why we thought it didn’t matter if Nixon or Humphrey won

As America lurches toward Election Day, it is clear that this will be a very close election. Humphrey has the entire Democratic establishment desperately working as hard as they can. They will not be enough in what will turn out to be an election decided by less than a percentage point.

Those of us in the student antiwar movement see Humphrey as profoundly corrupt, profoundly tainted by his support for the war. We hate Nixon, but in truth we have not experienced what a right-wing government can do. We have come of age and to activism in the years since 1960 — so we only know Kennedy and Johnson as presidents, we have only experienced a liberal domination of national politics, and, more often than not, the policies we are protesting are the policies of liberal Democrats.

In the fall of 1968, we experience a great failure of political imagination.

We think it doesn’t matter if Nixon or Humphrey wins. We think the war will keep going the same no matter who wins. We cannot imagine that it will expand, that there will be a simultaneous policy of "Vietnamization," so that the American body count decreases, and escalation that will claim another million more Asian lives. We cannot imagine the disaster that will befall Cambodia because of Nixon and Kissinger and the Christmas bombings of Hanoi and Haiphong. We do not see what is coming — at home as well as internationally.

We do not understand that soon Nixon will invite to the White House and celebrate the leaders of building trades unions who led violent attacks on antiwar protesters in New York. We think the well of black sadness cannot get any deeper. We are wrong. We cannot imagine what will be unleashed against black leaders and the black community. We do not imagine that the FBI and Chicago police will shoot and kill Black Panther leader Fred Hampton as he sleeps in his bed, possibly drugged.

We have no idea the damage that will be done.

We cannot conceive of the manipulative use of a "war on drugs" to go after black communities and the antiwar movement. As cynical and as sophisticated as we think ourselves to be, we cannot conceive of policies that, years later, Nixon’s top aide, John Ehrlichman would bluntly describe to Dan Baum of Harpers thusly:

The Nixon campaign in 1968, and the Nixon White House after that, had two enemies: the antiwar left and black people. … You understand what I'm saying?

We knew we couldn't make it illegal to be either against the war or black, but by getting the public to associate the hippies with marijuana and blacks with heroin. And then criminalizing both heavily, we could disrupt those communities. … We could arrest their leaders, raid their homes, break up their meetings, and vilify them night after night on the evening news. Did we know we were lying about the drugs? Of course we did.

Despite our growing dread, we do not imagine that protesting students will be gunned down at Kent State and Jackson State. That Hoover’s FBI will get the green light to go after Nixon’s enemies.

We have a failure of political imagination. We have a failure of moral imagination.

We sit out the election. We organize street protests. We march. We mock. We do not organize young people to vote in one of the closest elections in American history. There are tens of thousands of young people looking to us for direction. We do not say, "Make history. Swing this election to Humphrey and show how powerful we as a group now are." No, we say, "A plague on both your houses," and walk away.

Nixon wins. Without knowing it, we have missed our moment.

We failed to understand Nixon and what was at stake

Looking back, we young idealists and activists were not so much wrong in our assessments of Humphrey as we were totally wrong in our assessment of whether it matters if a corporate center liberal is elected over an insecure, unstable, right-wing candidate who does not respect the Constitution.

Our failure was not in our assessment of Humphrey but in our failure to understand Nixon and what was at stake. We could have turned the close election in favor of Humphrey. We could not have moved the election results by 5 points, but we certainly could have moved the needed one.

Our refusal to participate started a process of making our movement profoundly irrelevant. We allowed Richard Nixon to come to power.  We allowed a right-wing counter-reformation to hold power and warp American politics for most of the next four decades. Within our movement, we allowed militancy to replace strategy.

We would continue to march. Tens of thousands, hundreds of thousands of us would continue to protest the war. We shut down campuses. We helped organize returning veterans to join the fight against the war. Many long-term, positive, and enduring movements and changes in the country have their roots at least partially in our efforts. However, none of that changes the mistake made in 1968.

The great cost of the Nixon presidency

Any history with "ifs" is hugely problematic. I cannot predict with any confidence what a Humphrey administration would or would not have done. I am sure it would have had its share of evils. However, the difference between a president who is not doing enough for progress — even one wedded to the national security state — and one who is using the power of the office actively to reverse progress and mobilize racists, the xenophobic, and the elites against progress is enormous.

The toll of the Nixon administration is long and heartrending. Internationally, more than a million Cambodian lives lost and a million additional Vietnamese and Laotians killed. In South America, the cost is perhaps best symbolized by the pain of Chilean singer Victor Jara, as the soldiers in the US-backed coup against an elected socialist president first chop off the fingers of his guitar-playing hands and then shoot him dead.

Domestically there was a cost, too, as Nixon started the counter-reformation to the ’60s, flouted the Constitution, created enemy lists, launched the war on drugs that would eventually lead to mass incarceration, and cynically did everything he could to destroy the leadership of the black community and the antiwar movement.

We who want to revitalize our democracy, fight against inequality and for justice, and work for change need to be able to imagine a very different, exciting alternative future. We need that positive vision. However, we also need the imagination to understand how profoundly bad it can get when demagogues come to power.

The only way Donald Trump does not become president of the United States is if Hillary Clinton does

No, 2016 is not 1968 — but there is a lot of similar sentiment: disaffection with establishment politics, young people who care about justice, a Democratic candidate whom many of those young voters are not excited about.

Some supporters of Bernie Sanders seem intent on making the same mistakes we did in that fateful year of 1968. Some of the pioneering, innovative protesters who have created Black Lives Matter seem to share our 1968 disdain for electoral politics, as if elections and who is in power could be ignored in the struggle for profound social change.

Others, the perpetual Hillary haters of the left, once again suffer from a profound failure of imagination. Unable to imagine how bad it could become, they preach about refusing to be forced again to "settle for the lesser of two evils."

Young people may play a pivotal role in this election. For the very first time, "millennials" now are as large a group of potential voters as my tired generation, the baby boomers. The pool of younger voters is also far to the left of the older voters. The young once again have a moral passion that could produce real change.

But there is a world of difference between pools of potential voters and actual voters. Whether young voters will actually vote this November, and whom they will vote for if they do vote, is still very much up in the air.

Some Sanders supporters still say they will stay home. What is currently altering the dynamics of the race and whittling down Clinton’s lead is the attraction of younger voters to the third-party candidates, Libertarian Gary Johnson and Green Jill Stein. Where Obama in 2012 received 60 percent of voters under 30, when Johnson and Stein are included in the polls, Clinton is receiving only 31 percent of those voters. A significant group of Sanders supporters cannot bring themselves to support Clinton, the candidate of the establishment, no matter what the threat from Trump and no matter how hard Bernie campaigns for her.

A recent YouGov poll shows only 60 percent of Sanders supporters choosing Clinton, with Jill Stein getting 11 percent and Johnson getting 6 percent and many still undecided. If Clinton could get 80 percent of the Bernie voters to support her, she would be back at her comfortable lead of early August. As pollsters turn to quizzing the smaller pool of "likely voters," many of the groups that most oppose Trump diminish, as so many of those people do not actually make it to the polls.

The one irreducible fact of this bizarre election is this: The only way Donald Trump does not become president of the United States is if Hillary Clinton does. In any closely contested state, staying home or voting for a third-party candidate is, in its impact, a vote for Trump. It does not take a great leap of moral or political imagination to envision the damage a Trump presidency will bring to our nation and to the world.

The support for Sanders among younger voters, the organizers of the Black Lives Matters movement, and the urgent efforts of climate change activists, all led by young people, are all good signs and potentially powerful forces for change.

I only hope that our peculiarly American penchant for historical amnesia will not stop our new young leaders from learning from the mistakes of those of us who have gone before.

[Michael Ansara spent many years as an activist and an organizer. He was a regional organizer for Students for a Democratic Society; chair of the Harvard Strike Committee of 1969; a founder of the Old Mole, an underground newspaper; and a leader of national and regional anti-Vietnam War protests. Since then, he has founded and run two successful businesses. Currently he writes poetry  and is a co-founder and chair of the Board of Mass Poetry.]